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DOI: 10.1055/s-0037-1610859
Copper-Catalyzed Synthesis of Fused Imidazopyrazine N-Oxide Skeletons
This study was funded by Scientific and Technologic Research Agency of Turkey (TÜBİTAK) (grant numbers:115Z894).Publication History
Received: 29 November 2018
Accepted after revision: 21 December 2018
Publication Date:
22 January 2019 (online)
Abstract
N-Propargyl-2-aroylimidazoles synthesized and converted into the corresponding ketoximes. Under various conditions, several mono- and diketoxime imidazole derivatives were formed by converting the carbonyl or carbonyl and propargyl groups into oxime groups. N-Propargyl monooxime imidazole derivatives were cyclized by treatment with CuI to give various imidazopyrazine N-oxides. Several copper salts, such as CuOAc, CuSO4, and CuOTf, formed the same cyclization product. This cyclization reaction occurred only in the presence of Cu(I) or Cu(II) salts; other transition metals such as Au, Ag, In, and Fe did not yield cyclic products. The nucleus-independent chemical shift method was used to calculate the aromaticity of the bicyclic rings.
Supporting Information
- Supporting information for this article is available online at https://doi.org/10.1055/s-0037-1610859.
- Supporting Information
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References and Notes
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